Present television receivers, such as NTSC (National Television Standards Committee) television receivers, include video processing circuitry that typically must process a video signal conforming to only a single, predetermined video format. To optimize the picture produced by such a television receiver, various parameters within the receiver are adjusted. Some of the adjusted parameters, such as gamma correction, colorimetry correction and the like, are related to characteristics of the camera producing the television signal. Some of the adjusted parameters, such as luminance peaking, black stretch and the like, are related to characteristics of a display device used to display a video signal produced by the video processing circuitry. In any event, since the predetermined video format does not change, the adjusted parameters are typically adjusted to a nominal value once at the factory. Thereafter, the television receiver produces an acceptable picture that may be further adjusted to conform to a particular viewer's sensibilities.
Future digital television (DTV) receivers are expected to be implemented substantially in accordance with the transmission standards established by the Advanced Television Standards Committee (ATSC). A similar standard is the European Digital Video Broadcasting (DVB) standard. A compressed digital video system is described in the ATSC digital television standard document A/53, incorporated herein by reference. Moreover, the Moving Pictures Experts Group (MPEG) has promulgated several standards relating to digital data delivery systems. The first, known as MPEG-1, refers to ISO/IEC standards 11172 and is incorporated herein by reference. The second, known as MPEG-2, refers to ISO/IEC standards 13818 and is incorporated herein by reference.
The new DTV standards allow broadcasters to deliver virtually any format up to 1920.times.1080 pixels. As such, DTV receivers must be capable of receiving and processing a multiplicity of video formats. Therefore, a need exists in the art for a television receiver that is capable of receiving a multiplicity of formats and automatically adjusting video and other processing parameters depending upon the format of a particular received signal. Specifically, a need exists for a video processing system suitable for use in such a multiple format television receiver.